A multicopter is one type of a helicopter and a machine having, generally, three or more rotors and flying by rotating these rotors at the same time, while keeping balance.
Unlike a helicopter having two or fewer main rotors, a multicopter does not need to have a complex mechanism of its rotors themselves and, therefore, the multicopter is very easy to maintain and its airframe can be built at more inexpensive cost.
Since an acceleration sensor, an angular velocity sensor, etc. which have high performance and are easy to handle have recently become widespread at a reasonable price, by combining a control mechanism with these sensors, stable operation and very easy maneuverability are being realized, especially in a comparatively small airframe such as a model aircraft and a unmanned aircraft.
Because of such a feature, multicopters are being utilized for diverse operations, not only for hobby, such as model aircrafts. Now, multicopters equipped with three, four, six, or eight rotors are becoming popular and a multicopter airframe specialized for a purpose is becoming available, such as one moving at high speed and one capable of carrying heavy objects.